1. Field of the Invention
This invention relates to a portable computer, such as a notebook type personal computer, a word processor, and so on. More specifically, this invention relates to a portable computer equipped with an add-on battery which can be removably fitted to the apparatus main body.
As portable computers have become widespread in recent years, improvements in portability, battery life and operability have been required. To improve operability, a keyboard must be inclined. To improve portability, the size and weight of the portable computer must be reduced. To prolong the life of the battery, the battery capacity must be increased. As one of the means for increasing the battery capacity, an add-on battery is removably fitted to the portable computer.
2. Description of Related Art
The prior art technology for tilting the key face of a portable computer includes a technology which fits a turn-down-type tilt stand to a personal computer. According to the turn-down-type tilt stand of this prior art, however, a useless space remains between the bottom surface of the portable computer and the desk surface on which the portable computer is put when the tilt stand is turned up. For example, Japanese Unexamined Patent Publication (Kokai) No. 8-76879 discloses a prior art technology which disposes an external memory device in such a space.
Prior art technologies which increase the battery life while improving portability include a method which fits an add-on battery device to the portable computer, whenever necessary. For example, Japanese Unexamined Patent Publication (Kokai) No. 8-76898 and No. 8-76887 disclose a structure capable of removably fitting a battery pack to a portable computer. However, such a portable computer is more bulky even when the add-on battery device is not fitted than those portable computers which have similar function but do not have the function of the add-on battery device.
One of the fitting technologies of the add-on battery prepares a groove and a rail so that the add-on battery device can be slidably fitted onto the portable computer. According to this fitting technology of the add-on battery, however, the add-on battery cannot be fitted easily once the groove undergoes deformation due to change with time.
Japanese Unexamined Patent Publication (Kokai) No. 8-76889 discloses a connection structure for an information processing apparatus in which connector shell portions for a pair of connectors are formed on the housing of an extended unit, the shell portions and the housing having formed thereon the shell portions are integrally molded from a resin material, and metal plating is applied to the entire surface.
As described above, when the tilt stand is turned up in the conventional portable computer equipped with the turn-down type tilt stand, a space remains between the bottom surface of the portable computer and the desk surface on which the portable computer is placed, and the space cannot be effectively utilized. In the conventional portable computer having a removable add-on battery, the size is greater than the portable computer having no add-on battery device function, and the portability is therefore lower.
According to the prior art technology capable of fitting the add-on battery in which the battery is fitted to the portable computer by the slide system using the groove and the rail, the add-on battery cannot be fitted easily to the portable computer, if the groove or the rail once undergoes deformation due to a change with time, and fitting becomes difficult in some cases.